1. Field of the Invention
The present invention relates to an image forming apparatus for transferring a toner image carried on an image bearing member onto a recording material.
2. Related Background Art
A conventional electrophotographic technology includes a technology for transferring a toner image carried on an image bearing member onto a recording material by passing the recording material between the image bearing member carrying the toner image and a transfer roller.
In the technology, U.S. Pat. No. 6,516,179 discloses a method by which a recording material enters a transfer nip. An image forming apparatus disclosed in U.S. Pat. No. 6,516,179 includes a guide member for guiding the recording material toward a second transfer nip portion of an intermediate transfer belt. By providing the guiding member, a leading edge of the recording material is first brought into contact with the intermediate transfer belt, and then enters the second transfer nip portion in a manner that the recording material passes along the intermediate transfer belt.
On the other hand, in recent yeas, there is more demand for outputting a print including no margin on an edge of a recording material (hereinafter, referred to as “margin-less print”) even by the image forming apparatus adopting the electrophotographic technology. A demand for the margin-less print as prints used for a poster, a leaflet, a brochure, a catalogue, a flyer, and the like is emerging. In addition, in the market, there is an increasing demand for an image forming apparatus capable of printing both the margin-less print and a normal print (print with margins on edges thereof).
However, the method in the image forming apparatus disclosed in U.S. Pat. No. 6,516,179, by which the recording material enters the second transfer nip may cause a phenomenon in which the leading edge of the recording material scrapes off the toner image carried on the intermediate transfer belt in the case where the margin-less print is printed. The phenomenon in which the leading edge of the recording material scrapes off the toner image causes an image defect in which an image formed on the leading edge of the recording material is scraped off. In a case where the recording material secures a sufficient margin at the edge of the leading edge side, the image defect is less likely to be caused, but in a case of outputting the print including no margin, the image defect may be caused. Further, as in the image forming apparatus disclosed in U.S. Pat. No. 6,516,179, in a case where a transfer member brought into contact with an intermediate transfer member is used, there may be caused an adverse effect in which toner running out of the edge of the recording material, which is contained in the toner image formed on the intermediate transfer member, is adhered to the transfer member. Then, the toner adhered to the transfer member soils a rear surface of the recording material. In other words, in the case where the margin-less print is printed with the structure of the image forming apparatus disclosed in U.S. Pat. No. 6,516,179, the adverse effect which is not caused in printing a normal print (with margins on the recording material) is caused.